UPGRADING OF CONTINUOUS FRYING SYSTEM AND TO PROLONG AND MAXIMIZE THE UTILIZATION OF FRYING OIL WITHOUT USING CHEMICAL TREATMENT ON THE FRYING OIL

PERSIDANGAN KEBANGSAAN PERTAMA PROGRAM PEMINDAHAN ILMU (KTP 01) Prosiding KTP 51 (2013) 437-443 21 – 23 OGOS 2013 EQUATORIAL HOTEL, BANGI

ECO 56 - Soft copy available at - https://drive.google.com/ drive/folders/0ByBlFVsjNeg5MXFuUU9USS1qYU0 UPGRADING OF CONTINUOUS FRYING SYSTEM AND TO PROLONG AND MAXIMIZE THE UTILIZATION OF FRYING OIL WITHOUT USING CHEMICAL TREATMENT ON THE FRYING OIL Ng Kim-Soon1, Hamidon Bin Salleh2, Norrizam Bin Mohamad Jaat3, Mohd Faizal Bin Mohideen Batcha4, Teo Ezhi Esther5, Tay Wee Wong6 1,5 Faculty of Technology Management and Business, Universiti Tun Hussein Onn Malaysia, 86400, Batu Pahat, Johor. 2,3,4 Faculty of Mechanical and Manufacturing Engineering, Universiti Tun Hussein Onn Malaysia, 86400, Batu Pahat, Johor 6 Miaow Miaow Food Products Sdn. Bhd., Lot 2907, Jalan Sri Bengkal, Parit Sengkuang, Sri Gading, 83300 Batu Pahat, Johor. [email protected], [email protected], [email protected], [email protected], [email protected], [email protected] ABSTRACT - Batch fryer and continuous fryer are the most common deep frying systems available in snack food processing industry. Both the frying systems even though serve the same purpose, their operation structures and principles are different. From physical observation and chemical analysis data, it was found that even if under the same frying circumstances, oil degradation progress tends to be accelerated in continuous fryer compared to batch fryer. Waste oil has always substantially been used in continuous fryer and the cost of operation is 5 times that of batch frying although it has the advantage of using fewer workers to operate. Repeatedly used cooking oil can cause hypertension, affect the live and may in the long run lead to cancer, the National Poison Centre has warned if the oil is consumed by human and such deteriorated oil are discarded as waste. In this case free fatty acid test and other indicators are used to monitor the frying oil quality. Generally, where frying oil quality with free fatty acids (ffa) (%) of above 1.5, it should be discarded from use in the frying. In most factories, the practice is at the value of 2%. Frying oil deterioration is a critical issue in snack food processing. It is not only very costly, in term of quality, the flavor, aroma and texture of deep-fried snacks are depending largely on the quality and condition of the frying oil besides the hazardous aspect of passing the high ffa with the food to the consumer. From manufacturing cost perspective, other than the food itself, the frying oil is one of the most expensive food related costs. Therefore, this proposed project is to upgrade continuous frying system and to prolong and maximize the utilization of frying oil without using chemical treatment on the frying oil and to improve the processing line. It is a way to maintain cost competitiveness advantage in this industry. It also provides a strong effort towards food management – providing quality food to consumer as quality assured of not hazardous food and at competitive cost in selling the product both local and internationally. The problem of current continuous frying system include high oxidation of the oil, the heat transfer system including its flow rate, hot spot in this coil heating process system and inefficient filtering system causing the fast dropped in oil quality during frying, batch finishing process that is not integrated causing inconsistency in quality and lower productivity. Keywords: continuous frying system, food processing, free fatty acids

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PENAMBAHBAIKAN SISTEM PENGGORENGAN SELANJAR UNTUK MEMANJANGKAN JANGKA MASA DAN MAKSIMAKAN PENGGUNAAN MINYAK MASAK TANPA MENGGUNAKAN RAWATAN KIMIA ATAS MINYAK PENGGORENGAN ABSTRAK - Penggorengan kelompok dan selanjar adalah jenis sistem menggoreng yang paling biasa didapati di industri pemprosesan makanan ringan. Kedua-dua sistem penggorengan walaupun berfungsi untuk tujuan yang sama, struktur operasi dan prinsip-prinsipnya adalah berbeza. Dari pemerhatian fizikal dan data analisis kimia, didapati bahawa walaupun dalam keadaan menggoreng yang sama, degradasi minyak masak adalah lebih cepat pada penggorengan selanjar berbanding dengan penggorengan kelompok. Minyak yang telah merosok sering digunakan secara ketara pada penggorengan selanjar dan kos operasinya adalah 5 kali ganda daripada penggorengan kelompok walaupun ianya mempunyai kelebihan beroperasi dengan menggunakan bilangan pekerja yang kurang. Pusat Racun Negara telah memberi amaran bahawa minyak masak yang digunakan berulang kali untuk memasak, ia merosok dan jika dimakan oleh manusia ia boleh menyebabkan tekanan darah tinggi, menjejaskan kesihatan dan kemungkinan pada jangka masa panjang membawa kepada kanser. Dalam kes ini, ujian asid lemak bebas dan petunjuk lain telah digunnakan untuk memantau kualiti minyak goreng. Secara umumnya, kualiti minyak masak dengan asid lemak bebas (FFA) (%) yang melebihi nilai 1.5 perlu dibuang dan tidak digunakan untuk menggoreng. Kebanyakan kilang mengamalkan penggunaan pada nilai 2%. Kemerosotan minyak masak adalah isu yang kritikal dalam pemprosesan makanan ringan. Ia bukan sahaja sangat maha,l dari segi kualiti, rasa, aroma dan tekstur, makanan ringan goreng juga bergantung kepada kualiti dan keadaan minyak masak selain aspek bahaya FFA tinggi dibawahkan melalui makanan kepada pengguna. Dari perspektif kos pembuatan, selain daripada makanan itu sendiri, minyak masak merupakan salah satu kos berkaitan makanan yang paling mahal. Oleh itu, cadangan projek ini adalah untuk menambahbaik sistem penggorengan selanjar untuk memanjangkan jangka masa dan memaksimumkan penggunaan minyak masak tanpa menggunakan rawatan kimia pada minyak goreng dan untuk menambahbaikkan garisan pemprosesan. Ini akan memberi daya saing dari segi kos kepada industri ini. Ia juga merupakan usaha gigih ke arah pengurusan makanan - menyediakan makanan yang berkualiti kepada pengguna melalui jaminan kualiti makanan yang tidak berbahaya dan pada kos yang berdaya saing di pasaran tempatan dan antarabangsa. Masalah sistem menggoreng selanjar yang sediaada ini termasuk pengoksidaan minyak yang tinggi, sistem pemindahan haba termasuk kadar alirannya, “hot-spot” pada gegelung sistem pemanas dan sistem penapisan yang tidak cekap telah menyebabkan kemerosotan kualiti minyak dengan kadar yang cepat semasa menggoreng, dan proses penggorengan kelompok yang tidak diintegrasikan menyebabkan ketidak konsisten kualiti makanan dan produktiviti pengeluran yang lebih rendah. Katakunci: sistem penggorengan selanjar, pemprosesan makanan, asid lemak bebas

INTRODUCTION Frying oil deterioration is a critical issue in snack food processing. It is not only very costly, in term of quality, the flavor, aroma and texture of deep-fried snacks are depending largely on the quality and condition of the frying oil besides the hazardous aspect of passing the high ffa with the food to the consumer. From manufacturing cost perspective, other than the food itself, the frying oil is one of the most expensive food related costs. Therefore, this proposed project is to Upgrade Continuous Frying System and to prolong and maximize the utilization of frying oil without using chemical treatment on the frying oil and to improve the processing line. It is a way to maintain cost competitiveness advantage in this industry. It also provides a strong effort towards food management – providing quality food to consumer as Sekretariat Program Pemindahan Ilmu, Suite 125, Kompleks Eureka, Universiti Sains Malaysia, 11800 Minden, Pulau Pinang. Tel: +604 657 8870 Fax: +604 657 5444. E-mail: [email protected]

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quality assured of not hazardous food and at competitive cost in selling the product both local and internationally. The project defines a need required for the improvement of frying processes in snack food production, in optimizing the utilization of frying oil in continuous fryer and processes to ensure and safe-guard quality of the food produced besides upgrading to better continuous processes in the production line. From the literature reviews, many researchers concluded a continuous fryer maintains better oil quality compared to batch fryer, however, in this factory, and others in this region, the theories contradicted with findings in the real frying operations. The filtration system and the continuous processes are also in poor conditions. The deep frying process used in this Company is common in this industry and the results of the improvement can assist this industry to prosper. Thus, this project is to improve the continuous deep frying processing lines.

LITERATURE REVIEW The increasing patronage of fast food establishments and restaurants reflects the appeal of deep fried foods. Consistent production of these appetizing fried foods appears straightforward, but demands careful control of the frying operation itself. Problems of greasy, soggy food and poor frying fat life often arise when operators are unaware of good frying practice. Worse still is these food may be boiled using the high fatty acid oils which is poisonous to our human body. Cooking requires heat transfer from a heat source into the foodstuff. Heat conduction by air in an oven is relatively slow, total immersion of food in a liquid gives a rapid result if a suitably high temperature can be reached. Fats are capable of being heated to high temperatures, are reasonably stable and help improve the eating qualities of the food. Hence fats are ideal for deep frying. Characteristics of Boiling Cooking Oils When a fat is heated for a considerable time, oxidized and polymerized species form, largely from unsaturated fatty acids present in the fat. These species account for the chemical and physical changes seen in used fat. The oxidation rate is proportional to the amount of unsaturation and particularly poly-unsaturation of the fat. When fat deteriorates with high temperature use, the main changes seen are concern colour, viscosity, FFA and IV, foaming, smoking and polymer formation. The smoke point generally refers to the temperature at which a cooking fat or oil begins to break down to glycerol and free fatty acids, and produce bluish smoke. The glycerol is then further broken down to acrolein which is a component of the smoke. It is the presence of the acrolein that causes the smoke to be extremely irritating to the eyes and throat. The smoke point also marks the beginning of both flavor and nutritional degradation. Therefore, it is a key consideration when selecting a fat for frying, with the smoke point of the specific oil dictating its maximum usable temperature and therefore its possible applications. For instance, since deep frying is a very high temperature process, it requires a fat with a high smoke point. The smoke point for oil varies widely depending on origin and refinement (Wolke, 2007). The smoke point of oil does tend to increase as free fatty acid (ffa) content decreases and degree of refinement increases (Morgan, 1942 and Bockisch1998). Heating oil produces free Sekretariat Program Pemindahan Ilmu, Suite 125, Kompleks Eureka, Universiti Sains Malaysia, 11800 Minden, Pulau Pinang. Tel: +604 657 8870 Fax: +604 657 5444. E-mail: [email protected]

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fatty acid and as heating time increases, more free fatty acids are produced, thereby decreasing smoke point (a “burnt” oil can be toxic due to high ffa). It is one reason not to use the same oil to deep fry more than twice (Wolke, 2007). Intermittent frying has remarkably greater effect on oil deterioration than continuous frying (Amit, et al.,). The ideal cooking oil should contain higher amounts of monounsaturated and polyunsaturated fats, with a minimal or no saturated fats and trans fats. Unsaturated Fats: These fats can come from both animal and plant products. There are three (3) types:   

Monounsaturated Fats - Usually come from seeds or nuts such as avocado, olive, peanut, and canola oils. These fats are liquid at room temperature. Polyunsaturated Fats - Usually come from vegetables, seeds, or nuts such as corn, safflower, sunflower, soybean, cotton seed, and sesame seeds oils. These fats are liquid at room temperature. Trans Fatty Acids - Trans fats are produced when liquid oil is made into a solid fat, such as shortening or margarine. This process is called hydrogenation. Trans fats act like saturated fats and can raise your cholesterol level.

Different fats and oils have different uses. Each performs best within a certain range of temperature. Some are made for high heat cooking, while others have intense flavors that are best enjoyed by drizzling directly on food. Considerably above the temperature of the smoke point is the flash point, the point at which the vapors from the oil can first ignite when mixed with air. Free fatty acids contents in frying oil increase with the number of frying (Chung et al., 2004). Free fatty acid value is used to monitor the quality of frying oil. Thermal hydrolysis takes place mainly within the oil phase rather than water–oil interface (Lascaray, 1949). Short and unsaturated fatty acids are more soluble in water than long and saturated fatty acids. Water from foods is easily accessible to short-chain fats and oils for hydrolysis (Nawar, 1969). Warner et al., (1994) reported that the oxidation rate of oil increased as the content of unsaturated fatty acids of frying oil increased. Free fatty acids in frying oil accelerated thermal oxidation of the oil (Frega et al., 1999). The filtering of oil with adsorbents lowered free fatty acids and improved the frying quality of oil. As oxidation of the fat sets in, the quality of oil will drop as unsaturated fatty acids undergo oxidative reactions, and FFA (one of the breakdown products) will increase. If fresh fat can be regularly added to the fryer, the FFA of fat in the fryer can be maintained at workable levels. Free fatty acids and their oxidized compounds produce off-flavor and make the oil less acceptable for deep-fat frying. Generally fat with an FFA >1.5% should be discarded as there will be sufficient breakdown material present to rapidly catalyze further oxidation. Foaming becomes a severe problem when FFA >2.0% (Bakels edible oil). Cyclic compounds are not formed to a significant extent until the oil temperature reaches 200 to 300 degree Celsius. Polymers formed in deep-fat frying are rich in oxygen. Yoon et al., (1988) reported that oxidized polymer compounds accelerated the oxidation of oil. Polymers accelerate further degradation of the oil, increase the oil viscosity (Tseng et al., 1996), reduce the heat transfer, produce foam during deep-fat frying, and develop undesirable color in the food. Polymers also cause the high oil absorption to foods.

Performance of Heat Exchanger Increasing heat exchanger performance usually means transferring more duty or operating the exchanger at a closer temperature approach. This can be accomplished without a Sekretariat Program Pemindahan Ilmu, Suite 125, Kompleks Eureka, Universiti Sains Malaysia, 11800 Minden, Pulau Pinang. Tel: +604 657 8870 Fax: +604 657 5444. E-mail: [email protected]

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dramatic increase in surface area. This constraint directly translates to increasing the overall heat transfer coefficient, U. The overall heat transfer coefficient is related to the surface area, A, duty, Q, and driving force, ΔT. This equation is found in nearly all heat exchanger design references (Kern, 1950), . As stated in this form, U can be calculated from thermodynamic considerations alone. This calculation results in the required U such that the heat is transferred at the stated driving force and area. Independent of this required U based on thermodynamics, an available U can be determined from transport considerations. For this calculation, U is a function of the heat transfer film coefficients, h, the metal thermal conductivity, k, and any fouling considerations, f. An exchanger usually operates correctly if the value of U available exceeds the U required. For basic shell-and-tube exchangers, there are a number of literature sources that describe how to estimate heat transfer film coefficients based on the flow regime and the type of phase change: boiling or condensing (Kern, 1950; Perry and Green,1984; Hewitt, 1992; Ozisik, 1985). The precise calculation of U from the transport relationships accounts for all of the resistances to heat transfer. These resistances include the film coefficients, the metal thermal conductivity, and fouling considerations. The calculation of U is based upon an area. For shelland-tube exchangers, the area is usually the outside surface of the tubes. These coefficients do not necessarily represent final designs but are sufficient for estimating purposes . The overall heat transfer coefficient can also be calculated by equation , provided the inside and outside film coefficients, hi and ho, and the fouling resistance, f, are known. U can be calculated from the following simplified equation, provided the fouling resistance, and the metal thermal conductivity are not significant compared to the convective film coefficients. Also, the inside tube area must be approximately the same as the outside tube area . Note that even with no fouling considerations, the overall heat transfer coefficient is always less than one-half of the highest film coefficient (hi or ho) and usually in the neighborhood the of the lowest film coefficient. More detailed methods to calculate an overall film coefficient are provided in the references (Kern, 1950; Perry and Green,1984; Hewitt, 1992; Ozisik, 1985). Critical Issues On Cooking Oils Star Newspaper Exclusive Report On Cooking Oil News is also available in public newspaper to bring awareness of hazard of used cooking oil. Tuesday December 13, 2011 Don’t use oil more than once, warns poison centre. http://thestar.com.my/news/story.asp?file=/2011/12/13/nation/20111213064525&sec=nation PETALING JAYA: Repeatedly used cooking oil can cause hypertension, affect the liver and may in the long run lead to cancer, the National Poison Centre has warned. Centre consultant Dr T. Jayabalan said cooking oil should not be used even twice. “When used repeatedly, the concentration of hydrocarbons in the oil increases and these can clog and stiffen arteries, causing hypertension and also affect the liver,” he said in a phone interview. “Many people do not discard the oil after using it once. They put it in a container to be used again before they finally dispose of it,” Dr Jayabalan said.

Sekretariat Program Pemindahan Ilmu, Suite 125, Kompleks Eureka, Universiti Sains Malaysia, 11800 Minden, Pulau Pinang. Tel: +604 657 8870 Fax: +604 657 5444. E-mail: [email protected]

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“No level of contamination should be allowed. There is no basis for a permissible level of recyling for oil meant for human consumption.”

METHODOLOGY This project is divided into a five (5) phases: Phase 1 to Phase 5 of the project. The Flow chart, Project Gantt Chart with milestone is used to guide the phases of activities. The key activities are listed as follows. A. Application review and sites visits In this phase, an intense talk will be hold with the company’s operations to continue discussion the nature of the issues and information collection and to implement the solutions. The site of the where the frying equipments and processes line will be surveyed. Data pertaining to frying temperature, products specification, moisture contents and other parameters collected are further reviewed. B. Modification of frying equipment and process line. The information available from Phase A ensures the right equipments for the right jobs. The modified equipments when commissioned, a pilot run on the system is done, tested and analysed. Modify equipments where needed. C. Adjustment and larger scale integration The data analysed and information above used to fine tune the pilot run of the frying system to improve the improve the process of frying, product and frying oil quality, reduce product and oil quality variance during snack frying, optimize the production process from raw materials until end-product and minimize food waste. When the operation is satisfactory, integration will be conducted. Production fryer setup is ready, the performance of frying process, product and frying oil quality interactions during snack deep frying, oil quality indicators, free fatty acid and peroxide value by end point auto-titration, moisture content of the food determined by moisture analyzer is again used to gauge the success of the new line. D. Standardization of system Upon successful upgrading the production system, the new process is documented. ii. Flow Chart of Research Activities iii. Gantt Chart of Research Activities iv. Milestones and Dates (2 year Activities) November 2012

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November 2012 March 2013 September 2013 October 2013

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Commencement of project. Meeting with shop floor to discuss the direction of the project. Document issued Meetings and clarification Putting down in writing the technical specifications and description Review

Sekretariat Program Pemindahan Ilmu, Suite 125, Kompleks Eureka, Universiti Sains Malaysia, 11800 Minden, Pulau Pinang. Tel: +604 657 8870 Fax: +604 657 5444. E-mail: [email protected]

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Nov 2013

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January 2014 February 2014 March 2014

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May 2014

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May 2013 Jun 2014 August 2014

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Presentation of Plans, approval by Company Top Management and Commencement of Phase 2 of Project Commencement of Phase 3 of Project Test run 1, Adjustment and necessary modification Commencement of Phase 4 of Project: Test run 2, Adjustment and necessary modification Commencement of Phase 5 of Project: Test run 3, Adjustment and necessary modification Test run 4, Necessary adjustment and modification Implementation and new processes documentation Run at the production line and sops documentation

REFERENCES 1. Amit K. Das, et al., (-). http://www.slideshare.net/amitkdas12/study-of-oil-deterioration-duringcontinuous-and-intermittent-frying 2. Bakers Edible Oil, Deep Frying, ‘More Of An Art Than A Science', Accessed on 28 June, 2012. 3. Bockisch, Michael (1998). Fats and Oils Handbook. Champaign, IL: AOCS Press. pp. 95–6. ISBN 0935315829. http://books.google.com/books?id=ixEtWwg72OQC. 4. Chung, J., Lee, J. and Choe, E.(2004). Oxidative stability of soybean and sesame oil mixture during frying of flour dough. Journal of Food Science, Vol. 69, 574–8. 5. Frega, N., Mozzon, M., and Lecker, G. (1999). Effects of free fatty acids on oxidative stability of vegetable oil. Journal of the American Oil Chemists' Society, Vol. 76, 325 - 329. 6. Gulley, D.(1996), “Troubleshooting Shell-and-Tube Heat Exchangers,” Hydrocarbon Processing, Vol. 75(9), 91-98, September. 7. Hewitt, G.F.(1992), Handbook of Heat Exchanger Design, Begell House, Inc., New York, New York. 8. Kern, D.Q. (1950), Process Heat Transfer, McGraw-Hill, Inc., New York. 9. Lascaray, L. (1949). Mechanism of fat splitting. Industrial Engineering Chemistry,Vol. 41, 786–90. 10. Morgan, D. A. (1942). "Smoke, fire, and flash points of cottonseed, peanut, and other vegetable oils". Oil & Soap 19: 193. doi:10.1007/BF02545481.edit 11. Nawar, W.W. (1969). Thermal degradation of lipids – A review. Journal of Agricultural and Food Chemistry, Vol. 17, 18–21. 12. Ozisik, M.N. (1985). Heat Transfer: A Basic Approach, McGraw-Hill, Inc., New York, New York, 1985. 13. Perry, R.H., and D. Green. (1984), Perry’s Chemical Engineers’ Handbook, 6th ed., McGraw-Hill, Inc., New York. 14. Tseng Y.C., Moreira, R.G., and Sun, X. (1996). Total frying - use time effects on soybean oil deterioration and on tortilla chip quality. International Journal of Food Science & Technology, Vol. 31, 287-294. 15. Warner, K., Orr, P., Parrott, L. and Glynn, M. (1994). Effects of frying oil composition on potato chip stability. Journal of the American Oil Chemists' Society, Vol. 71, 1117–1121. 16. Wolke, Robert L. (May 16, 2007). "Where There's Smoke, There's a Fryer". The Washington Post. http://www.washingtonpost.com/wpdyn/content/article/2007/05/15/AR2007051500398.html. Retrieved March 5, 2011. 17. Yoon, S.H., Jung, M.Y., and Min, D.B. (1988). Effects of thermally oxidized triglycerides on the oxidative stability of soybean oil. Journal of the American Oil Chemists' Society, Vol.65(10), 1652 - 1656.

Sekretariat Program Pemindahan Ilmu, Suite 125, Kompleks Eureka, Universiti Sains Malaysia, 11800 Minden, Pulau Pinang. Tel: +604 657 8870 Fax: +604 657 5444. E-mail: [email protected]